THE BROWN ROT DISliASE OF THK RKDWOOJ). 



81 



tie harm. The disease may possibly develop in timlxT that was partly 

 decayed when cut from the tree, although in several cases observed 

 such timber was used for posts or ties and did not deteriorate further. 

 Where strength is not the first requirement, wood in the early stages 

 of decay may be classed in a low grade for posts or ties. , 



Measures for preventing decay in Redwood are impracticable. 



DECAY IN REDWOOD POLES. 



As this bulletin goes to press the writer is in receipt of samples of 

 decayed Redwood taken from telegraph poles in California that were 

 set in 1877. They were 12 inches square at the butt and were set 5 

 feet into the ground. About half of them showed signs of decay this 

 year; half of this number had decayed from the outside in, while the 

 other half showed rot within the poles. Many poles that were broken 

 ofl' by a windstorm had been decayed to a depth of several inches. 



The decay very closely resembles the red rot. The diseased wood 

 is red-brown, brittle, and porous. In cases where the decay started 

 on the outside, the spring wood cells were attacked first, leaving the 

 sunmier cells practically intact. In the deca3'ed wood many colorless 

 hyphfe traverse the walls, and here and there are found groups of 

 colored spores. No fruiting organs of any fungus occurred on the 

 samples sent. 



PREVENTION. 



The decay of poles of the Redwood can probabl}^ be retarded consid- 

 erably by thoroughly drying the poles before setting them. Careful 

 inspection will often show, at the butt end, signs of the brown rot 

 disease of the living tree. Poles from such trees should not be used. 

 Dry poles can be coated with some preservative substance, which will 

 probablj^ retard decay considerably. Tests are now under way with 

 the Redwood to determine the best method for preventing this rot. 



EXPLANATION OF PLATES. 



Plate X. Cross sections of Redwood logs (Fort Bragg, Cal. ), showing brow-n-rot 

 disease. Fig. 1 shows distribution of pockets. Since the log lies partly 

 in a stream, only a part of the section is exposed. Fig. 2 shows a small 

 part of a section with pockets in various stages. 



Plate XI. Tangential section of Redwood log, showing the decayeil wood in long 

 pockets. 



